Subasic said Monaco's players were informed of the situation by head coach Leonardo Jardim and expressed his concern for Bartra and any other injured parties.

"I'm alive, everything is fine, we are in the locker room at the stadium," he told 24sata.

"We were preparing for the game when the coach entered and told us that the match was postponed because one player of Borussia was injured by an explosive device.

"We are in the stadium, safe, but the feeling is terrible. Rather than run out in front of a full stadium and play in a Champions League match, we sit quietly in the locker room and think about where all of this leads.

"I hope that Bartra, or anyone that was hurt, will be okay."

Police said there was no danger to anyone inside Signal Iduna Park, where thousands of fans had already gathered when the explosion happened approximately an hour before the scheduled kick-off time.

Dortmund tweeted their thanks to Monaco fans who were chanting the club's name in a show of solidarity.

Juventus' quarter-final first leg with Barcelona went ahead as planned in Turin.